1. Field of the Invention
The present invention relates generally to X-ray radiography, and more particularly relates to radiation inspection devices and methods for detecting the presence of high-z materials in containers.
2. Related Art
The detonation of a nuclear weapon in a major city is perhaps the worst terrorist threat imaginable, with casualties and property damage likely exceeding those of past terrorist attacks by a factor of ten or a hundred or even more. The shipping and transportation industry is considered at risk for terrorist activity due to the high volume of containers that moved across borders and low inspection rates. For example in the United States, approximately 7,000,000 cargo containers enter the country by sea each year and about 9,000,000 by land, in addition to the thousands of cargo containers that enter the country by air. Since existing inspection methods are insufficient in detecting the presence of nuclear weapons, each of the containers must be opened and inspected manually. Inspecting each container manually would be time consuming and cause major delays. Thus, of these millions of containers only a comparatively few are opened for inspection, thereby offering a terrorist a potential opening for smuggling a nuclear weapon into a country.